<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <script src="https://cdn.jsdelivr.net/npm/vue@2.6.14/dist/vue.js"></script>
    <title>Document</title>
</head>
<body>
    <div id="app">
        <ul>
           <item :num="list" v-for="(num, index) in list" :key="index">{{num}}</item>
        </ul>

        <button @click="change">change</button>
    </div>

    <script>
        let app = new Vue({
            el: '#app',
            data() {
                return {
                    list:[
                        1,2,3
                    ]
                }
            },
            methods: {
                change() {
                    this.list.reverse()
                }
            },
            components: {
                item: {
                    props: ['num'],
                    template:`
                    <div> {{num}} </div>
                    `
                }
            }
        })
    </script>
</body>
</html>